reach, arrive, manage
蒞 centers on arriving at a place or situation and then taking charge: reaching a destination, arriving to manage affairs, or assuming control.
蒞 is a rare character. It visually combines 艹 (grass) on top and 涖 (water arriving) below, but the exact historical development is uncertain. It may be a variant or later form of 莅, which uses 亻 (person) instead of 氵.
Grass 艹 on top and water 氵 arriving below with a standing figure 立: imagine reaching a grassy shore where water meets land, and then managing the landing.
For リ, picture reaching a riverbank and needing to manage the landing: river -> リ, and you arrive to take charge.